A Palladium(II)‐Catalyzed Synthesis of α‐Ketoamides via Chemoselective Aroyl Addition to Cyanamides

Abstract

An acyl moiety generated from a-oxocarboxylic acids via decarboxylation undergoes a palladium-catalyzed chemoselective insertion into organic cyanamides to afford N-monosubstituted a-keto-Scheme 3. Substrate scope for the formation of a-ketoamides. Reaction conditions: cyanamide (0.5 mmol), glyoxalic acid (0.5 mmol) at 80 8C for 2 h. Isolated yields are given. 2562

Metal‐Free C=C Double Bond Cleavage on Enaminones for the Synthesis of α‐Ketoamides by Free‐Radical Aerobic Oxygenation

“…To date, a plethora of synthetic methods have been reported to be capable of affording α‐ketoamide scaffolds. For instance, the oxidation on pre‐functionalized precursors such as hydroxyl amides, haloamides or aminoamides; the amidation of α‐ketoacids or acyl chlorides, the C‐H amidation of α‐ketoaldehydes, the oxoamidation of simple aldehydes and ketones, the oxoamidation of α‐hydroxyl or ester functionalized ketones, the aminocarbonylation reaction using isocyanides, the oxidative oxoamidation of α,α‐dihaloketones, the oxoamination reactions based on the cleavage of C‐C single bonds, C=C double bond and C≡C triple bonds, and others …”

Synthesis of α‐Ketoamides via Electrochemical Decarboxylative Acylation of Isocyanides Using α‐Ketoacids as an Acyl Source

“…They are considered as more environmentally friendly acylation reagents in the acylation reaction since carbon dioxide is the only by‐product produced from the reaction [10] . Several strategies for synthesizing α‐ketoamides using α‐ketoacids as an acyl source have been developed; among which, the trans‐metal‐catalyzed decarboxylative acylation reaction was the first reported reaction (Scheme 1, A) [11–13] . However, these methods suffer from the requirement of metal catalysis, the addition of stoichiometric peroxide or persulfide, and the need of high temperature.…”

“…[10] Several strategies for synthesizing αketoamides using α-ketoacids as an acyl source have been developed; among which, the trans-metal-catalyzed decarboxylative acylation reaction was the first reported reaction (Scheme 1, A). [11][12][13] However, these methods suffer from the requirement of metal catalysis, the addition of stoichiometric peroxide or persulfide, and the need of high temperature. Recently, Wei and team have reported light mediated decarboxylative acylation of isocyanides using Rose Bengal as a photo catalyst to synthesize α-ketoamide under mild conditions in the absence of oxidants and transition metals (Scheme 1, B).…”

Progress on the Synthesis and Applications of Cyanamides

“…22). Patel 等[56] 发展了钯催化氰胺 109 和 α-酮酸 110 的串 联反应高效合成 α-酮酰胺类化合物 111 (Scheme 20). 在 氧化条件下, Pd(O 2 CCF 3 ) 2 催化 α-酮酸和氰胺发生多步 串联反应生成中等偏上产率的 α-酮酰胺类化合物, 对卤 素、氰基等官能团具有良好的兼容性.…”